Robin Williams says he is a "work-in-progress" dad

LOS ANGELES (Reuters) - Robin Williams stars in a movie called "World's Greatest Dad," but as a real life father of three grown kids the Oscar winner said he had to overcome dark times and was still a work-in-progress.

"I'm so proud of them in different ways, but have they always been cherubs? No, but that's been part of the process," Williams said in an interview.

"And am I the 'world's greatest dad?' Not at all, I'm a work-in-progress, but I love them," said Williams, whose latest of 51 movies opens on Friday.

A son from his first marriage, Zachary, 26, graduated from New York University. From his second marriage were born Zelda, 20, a budding actress, and Cody, who turns 18 this year.

The comic, who in the past has entered rehab to deal with substance abuse, said his difficulties gave his children a ready response when he questioned them about their behavior.